MILAN, September 17, 2013 (AFP) - The mother of former Tour de France champion Marco Pantani has called to re-open the inquest into his death because she suspects he was the victim of foul play.

Italian star Pantani, the winner of the Tour de France and Giro d'Italia in 1998, officially died of a cocaine overdose at the Le Rose Hotel in Rimini on February 14, 2004. But after recently studying court documents, his mother Tonina believes many questions still remain unanswered.

She suggested the death of Pantani, suspected of using performance-enhancing drugs throughout his career and known later to have cocaine problems, could have been facilitated by figures keen to stop him from exposing the extent of drug use in the peloton.

"I've asked for the re-opening of the investigation because I want explanations, I want answers," she told the Mattino Cinque television program. "I want to know how he died. My biggest concern is that he may have been killed. In my opinion, Marco had ruffled someone's feathers. He spoke his mind and talked about doping, that doping was a big problem."

Earlier this year, a damning French parliamentary commission said Pantani and several other cycling stars had used the banned blood booster EPO (erythropoietin) during the 1998 Tour de France.

It was the cyclist's last Grand Tour victory and came two months after he won the Giro d'Italia.

Pantani remains the last cyclist to achieve the Tour-Giro double. As he faced ongoing allegations of drug use, he went into depression and never really recovered.

His death in 2004 was attributed to acute cocaine poisoning, but Tonina says recent documents released from the court contain "false" accusations.

"I've seen the court documents and there are things written in there which are just not true," she added.

She notably claims Pantani may not have been alone in the hours leading up to his death.

"Marco wasn't alone in the Rimini residence where he was found dead: There could have been other people with him," she said. "He called the police, complaining of people who were bothering him and an hour later he was found dead."